The Italian conductor, Ruben Jais, while studying Medicine at Università Statale, graduated at the Conservatory Giuseppe Verdi of Milano in Choral Music and Chorus Cunduction and Vocal Poliphonic Composition, both degrees with Honour. At the same Conservatorio he also graduated in Composition and studied Orchestra Conducting, continuing his studies then with master-classes abroad.

Ruben Jais is conductor of the Symphonic Chorus Giuseppe Verdi of Milano since it was founded in 1998 until 2007. In this role he worked with such musicians as Romano Gandolfi, Riccardo Chailly, Claudio Abbado, Luciano Berio, Oleg Caetani, Claus Peter Flor, Christopher Hogwood, Vladimir Jurowski and Helmuth Rilling, among others. He is Resident Conductor and Head of the Artistic Department of the Orchestra Sinfonica di Milano Giuseppe Verdi. He had several concerts with this Orchestra and conducted many series of concerts like "Storia in Musica", that wants him and his Orchestra to execute the repertoire from the Reinassance to the Last Romanticism and to explain the meaning of musical pieces during the concert, "Crescendo in Musica", a series of concerts that is thought for a younger public, and the series of J.S. Bach's "Cantate Profane" (Secular Cantatas). He also conducted Baroque Operas like H. Purcell's The Fairy Queen with the Symphonic Orchestra and the Symphonic Chorus Giuseppe Verdi of Milano and the soloists of Yale University.

In 2008 Ruben Jais founded LaVerdi Barocca, ensemble devoted to the performance of Baroque and classical repertoire on period instruments; with such ensemble he holds a concerts season at the Auditorium di Milano, seat of the Verdi Foundation, performing from 16th century to early classical period music. Since September 2005, he is Artistic Director of Mailänder Kantorei, a group that is close to the German Community of Milano, with which he performes a German repertoire from its Baroque to its Romanticsm, including the performance of J. S. Bach's Sacred Cantatas Cycle and Passions. He is also Artistic Director of the Camerata Polifonica RJ, with which he prefers a Baroque and a contemporary repertoire.